If you are looking for a clue to how Jimmy Garoppolo will answer the bell on the biggest and brightest stage of his football life — with the ghost of Tom Brady hovering over University of Phoenix Stadium on Sunday night against the blitz-crazed Cardinals, and without TE Rob Gronkowski — let’s check in with the man who coached him the day he threw seven touchdown passes for Eastern Illinois against Illinois State three Septembers ago.

“They did some things to us after the snap … something that the coaches couldn’t change, but the quarterback could have changed on the field,” Dino Babers, now the Syracuse coach, told The Post. “What it came down to was whether Garoppolo had enough knowledge for us to take the handcuffs off of him to let him operate with certain calls at the line of scrimmage, kind of the way that a lot of quarterbacks do in the NFL. But it had never been done before with our guys.

“A lot of the coaches voted no,” Babers said with a chuckle, “and everybody gets a vote on our staff, that’s the way we operated. I voted yes. Based off of his personality, I thought how his first two years he had been under center and he had been trained by Roy Wittke, who was the same guy that recruited and trained Tony Romo, that Jimmy Garoppolo was just different than other spread quarterbacks.

“So what we basically did is we kind of combined the spread offense with some underneath-center principles, and Illinois State had no idea that we had done that. So we came in the game, and they were doing some very, very exotic blitzes thinking that they were gonna get home, and we wouldn’t have been able to change the plays to the perfect calls on the sideline. But if you had a quarterback that knew what they were doing, they could change the plays to the perfect calls on the field, and the rest is history. I mean, it was bad. When I say bad, it was bad for them, it was really, really good for us. Jimmy did an unbelievable job in that game.”

For Garoppolo, this is the first of four personal Super Bowls, a referendum on how good of a sponge he has been over the past two seasons soaking up the Brady Way and the Patriots Way.

Defategate for him, and for the Patriots as they begin their quest for an eighth consecutive division title.

“I think he’s gonna do just fine,” Babers said. “I think he’s been in those situations before. He’s been a smaller fish in a bigger pond, so to speak, his entire life, being overlooked by Division I programs, going to one of the top FCS programs in Eastern Illinois. And then having to play Division I programs and knocking ’em down and playing fabulously, being a small fish playing on a bigger stage. So I just think all that will transfer along with all the knowledge that Bill Belichick and his staff has given him, and sitting there watching Tom Brady for a couple of years, I just think that he’s gonna be a little bit better off than the average guy stepping into that situation.”

Garoppolo has thrown exactly 31 NFL passes, all of them properly inflated. He is the substitute teacher taking over Professor Brady’s class. But he is no patsy. He is a highly intelligent and highly competitive football addict, armed with a quick release, precision accuracy, moxie and, of course, greater mobility than Brady.

Even as a high school outside linebacker, Garoppolo always has embraced the spotlight. The moment won’t be too big for him. He won’t be Jimmy G Whiz.

Garoppolo at Eastern Illinois in 2013AP

Rolling Meadows (Ill.) H.S. teammate and wide receiver Mick Viken: “Everybody believes in him in the huddle. He’s easy to get behind and rally behind because he’s a friend to everybody.”

They played together for the Arlington Knights in middle school. Viken was a pole vaulter at Eastern Illinois.

“People flock to him,” Viken said. “He certainly takes command of the huddle. incredibly sure of his own ability.”

Garoppolo’s task will be to manage the game and try to find a way to win in the fourth quarter. And hand the football and nothing worse than a 2-2 record back to His Twelveness.

“He’s one of the most humble people that I’ve ever gotten to know,” Viken said.

Garoppolo may be the favorite over Brady on “The Bachelor,” but no one should expect No. 10 to be the Perfect 10. No one should expect him to be The Deflator either.